US5161521A - Oscillation degree measuring apparatus - Google Patents

Oscillation degree measuring apparatus Download PDF

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Publication number
US5161521A
US5161521A US07/603,621 US60362190A US5161521A US 5161521 A US5161521 A US 5161521A US 60362190 A US60362190 A US 60362190A US 5161521 A US5161521 A US 5161521A
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United States
Prior art keywords
oscillation
oscillations
ultrasonic
degree
signals
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
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US07/603,621
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English (en)
Inventor
Yoichi Kasahara
Hisatsune Kadota
Norio Kaneko
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Nikon Corp
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Nikon Corp
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Assigned to NIKON CORPORATION, A CORP. OF JAPAN reassignment NIKON CORPORATION, A CORP. OF JAPAN ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: KADOTA, HITSATSUNE, KANEKO, NORIO, KASAHARA, YOICHI
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
    • G01M7/00—Vibration-testing of structures; Shock-testing of structures
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
    • A61C19/00—Dental auxiliary appliances
    • A61C19/04—Measuring instruments specially adapted for dentistry
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01H—MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
    • G01H13/00—Measuring resonant frequency
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
    • G01M7/00—Vibration-testing of structures; Shock-testing of structures
    • G01M7/02—Vibration-testing by means of a shake table
    • G01M7/025—Measuring arrangements
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
    • G01N29/04—Analysing solids
    • G01N29/12—Analysing solids by measuring frequency or resonance of acoustic waves
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2291/00—Indexing codes associated with group G01N29/00
    • G01N2291/02—Indexing codes associated with the analysed material
    • G01N2291/024—Mixtures
    • G01N2291/02483—Other human or animal parts, e.g. bones

Definitions

  • the present invention relates to a measuring apparatus for inspecting a fixing state of an object to a supporting member, and more particularly to an oscillation degree measuring apparatus for inspecting a fixing state of a small object, such as the root of a tooth.
  • a dental implant (the root of a tooth) is given as an example of an object whose fixing state is required to be measured.
  • the fixing state can be thought of as the degree of oscillation of an object to be measured.
  • the degree of oscillation means the amount of oscillation of the object to be measured when a certain shock is given to the object.
  • the inventors of the present invention invented an apparatus for measuring slight oscillations of an implant by ultrasonic waves and diagnosing the fixing state of the implant, which has been already disclosed in Japanese Patent Application Laid-open No. 60-190941.
  • the disclosed apparatus transmits ultrasonic oscillations, which are generated from an ultrasonic oscillation source and include at least a predetermined resonant frequency element, to an implant buried in a jaw bone through an ultrasonic wave transmitting means, detects the oscillations excited by the implant by a detection means, converts a resonant phenomenon at the above predetermined resonant frequency into electrical signals and observes the electrical signals, and diagnoses the fixing state of the implant based on whether or not the resonant phenomenon is present.
  • an oscillation degree measuring apparatus of the present invention comprises an ultrasonic exciting means for generating ultrasonic waves which shock an object to be measured and exciting oscillations, an oscillation detection means for detecting the oscillations of the object to be measured and converting the oscillations into electrical signals, a band amplifying means for extracting a signal element of a predetermined frequency band including a resonant frequency of the object to be measured from the detected signals from the oscillation detection means, a smoothing circuit means for smoothing the signals amplified by the band amplifying means, an A/D converter means for converting the signals smoothed by the smoothing circuit means into digital signals, a control means for operating the A/D converter means a plurality of times every time a predetermined time passes, and a data processing means for finding an average value of a plurality of digital data obtained by the A/D converter means and calculating the degree of oscillation based on the average value.
  • the oscillation degree measuring apparatus of the present invention can measure the fixing state of a small object, for example, a buried dental implant, as a numerical value of the degree of oscillation and simply and precisely judge and evaluate the fixing state of the buried small object.
  • FIG. 1 is a block diagram showing the composition of an oscillation degree measuring apparatus of the present invention
  • FIGS. 2A and 2B are signal waveform charts explaining operations of the oscillation degree measuring apparatus shown in FIG. 1;
  • FIG. 3 is a block diagram schematically showing the composition of a more detailed embodiment of the present invention.
  • FIG. 5 is an operational flowchart showing measurement processes by the embodiment shown in FIG. 3.
  • FIG. 1 is a block diagram schematically showing the composition of an oscillation degree measuring apparatus of the present invention
  • the oscillation degree measuring apparatus comprises an ultrasonic exciting means composed of a pulse voltage generator 1 for transmitting ultrasonic oscillations to an object 12 to be measured through an oscillation transmitting member 3A and exciting the oscillations and an ultrasonic oscillator 2, and an oscillation detection means including an ultrasonic explorer 4 for detecting the oscillations of the object 12 to be measured through an oscillation transmitting means 38 and converting the detected oscillations into electrical signals, in the same manner as the apparatus disclosed in Japanese Patent Application Laid-open No. 60-190941.
  • the apparatus of the present invention further comprises a band amplifying means composed of an amplifier 5 for extracting a signal element of a predetermined frequency band including a resonant frequency of the object 12 to be measured from the signals obtained by the oscillation detection means and a band pass filter 6, a smoothing means including a smoothing circuit 7 for smoothing the signals amplified by the band amplifying means, an A/D converter means including an A/D converter 8 for converting the signals smoothed by the smoothing means into digital signals, a control means including a control device 10 for operating the A/D converter means a plurality of times every time a predetermined time passes and a data processing means including a data processing device 9 for finding an average value of a plurality of digital data obtained by the A/D converter means, calculating the degree of oscillation based on the average value and displaying the degree of oscillation in a display means including a display device 11.
  • a band amplifying means composed of an amplifier 5 for extracting a signal element of a predetermined frequency band including a
  • Ultrasonic oscillations including a resonant frequency of the object 12 to be measured are generated by the excitement of the ultrasonic oscillator 2 by electrical pulse signals generated by the pulse voltage generator 1, and the object 12 to be measured, such as a dental implant, is resonated through the oscillation transmitting member 3A.
  • the oscillations of the object 12 are transmitted to the ultrasonic explorer 4 through the oscillation transmitting member 3B, converted into electrical signals by the ultrasonic explorer 4 and detected.
  • the detected signals from the ultrasonic explorer 4 amplified by the amplifier 5 and only a signal element of a predetermined frequency band including a resonant frequency of the object 12 is taken out by the band pass filter 6.
  • the band of the band pass filter 6 is determined by the state of an object to be measured and so on.
  • the signals penetrating the band pass filter 6 form, for example, a damped oscillation wave form shown in FIG. 2A.
  • an envelope of the damped oscillations is found by the smoothing circuit 7 as shown in FIG. 2B.
  • the A/D converter 8 By operating the A/D converter 8 a plurality of times every time a predetermined time passes according to the control of the control device 10, damped envelope signals are measured.
  • An average value of a plurality of measurement data obtained by the A/D converter 8 is found by the data processing device 9, and the average value or a value obtained by multiplying the average value by a predetermined coefficient is displayed in the display means 11 as a measurement value of the degree of oscillation.
  • the measured degree of oscillation is a small value.
  • the fixing state of the object 12 is insufficient, since the oscillation is slowly damped, the measured degree of oscillation is a large value. It is possible to aptly and objectively evaluate the fixing state of the object to be measured based on the degree of oscillation obtained as these measurement values.
  • An average value of the degree of oscillation obtained in a plurality of measurements is found by the data processing device 9, a final measurement value is determined and displayed in the display device 11.
  • a process of, for example,multiplying the measurement value by a predetermined numeral may be performed by the data processing device 9. Furthermore, if the values obtained in a plurality of measurements greatly differ, it may be judged that the influence of the movement of the ultrasonic explorer cannot be eliminated and the judgement result may be displayed.
  • FIG. 3 is a block diagram of a more detailed embodiment of the present invention.
  • a pulse voltage generator 1 repeatedly generates rectangular pulse voltage having the pulse width of 10 ⁇ sec and the amplitude of 2 to 10 V every 1 msec as shown in FIG. 4A.
  • the pulse voltages from the pulse voltage generator 1 are converted into ultrasonic oscillations by an ultrasonic oscillator 2 and excite resonant oscillations in a dental implant 12 as an object to be measured through one oscillation transmitting member 3A.
  • the ultrasonic oscillator 2 to be used is, for example, a piezoelectric element of 3 mm in diameter with a stainless rod of 1 mm in diameter and approximately 30 mm in length as the oscillation transmitting member 3A attached thereto.
  • the oscillations excited in the implant 12 are transmitted through the other oscillation transmitting member 3B and converted into electrical signals by an ultrasonic explorer 4.
  • the ultrasonic explorer 4 to be used is, like the ultrasonic oscillator 2, a piezoelectric element of 3 mm in diameter with a stainless rod of 1 mm in diameter and approximately 30 mm in length as the oscillation transmitting member 3B attached thereto.
  • the electrical signals converted by the ultrasonic explorer 4 are faint, they are amplified to, for example, 1000 times thereof by the amplifier 5.
  • the amplified signals from the amplifier 5 are passed through, for example, a fifth-order Butterworth band pass filter 6 which allows only the element having the frequency of 10 to 20 KHz to pass therethrough.
  • the signals passing the band pass filter 6 form a damped oscillation waveform shown in FIG. 4B and repeated every time a pulse voltage is generated.
  • an appropriate type of filter such as a Chebyshev filter and an apposite Chebyshev filter, may be used as the band pass filter 6.
  • the output signals of the band pass filter 6 are given to a smoothing circuit 7 and the outputs of the smoothing circuit 7 form a signal waveform representing an envelope of a damped oscillation waveform shown in FIG. 4C.
  • the signal voltage of the envelope output from the smoothing circuit 7 is converted into digital signals by operating an A/D converter 8 three times that is, 0.1 msec, 0.3 msec and 0.5 msec after the voltage is generated in response to a control signal, shown in FIG. 4D, from a control device 10 which is realized by a CPU 15, and measured. Finally, an average value of the three digital signals is calculated as the degree of oscillation by a function of the data processing device 9 which is realized by the CPU 15.
  • the above measurement is repeated under the control of the control device 10 of the CPU 15, for example, 640 times and an average value of the obtained 640 measurement values is calculated by the data processing device 9.
  • a value obtained by multiplying the average measurement value, by for example, the coefficient 50, is regarded as a final measurement degree of oscillation and displayed in a display 11 using a liquid crystal panel.
  • the coefficient 50 by which the average value of the 640 measurement values is multiplied is determined so that the degree of oscillation is 100 when a model in the worst fixing state is measured.
  • FIG. 5 is an operational flowchart showing measurement processes of the present invention.
  • Step S1 the CPU 15 judges in Step S1 ("Step" is omitted hereinafter) whether or not a measuring period of 1 msec has passed. If the measuring period of 1 msec has passed, an ultrasonic transmission operation is performed in S2, a pulse voltage is generated by the pulse voltage generator 1, and oscillations are excited in the implant 12 through the ultrasonic oscillator 2 and the oscillation transmitting member 3A. After the ultrasonic transmission operation is performed in S2, it is watched in S3 whether or not 0.1 msec has passed since the oscillation was applied. When 0.1 msec has passed, received data is taken in S4.
  • an average value is calculated by dividing the sum total of 640 average measurement values by 640 in S11, the degree of oscillation is found by multiplying the average value by the coefficient 50, and finally, the numeral value is displayed in the display device in S13 and a series of processes are completed.
  • the measured value of the degree of oscillation is visually displayed in the display device 11 in the above embodiment, for example, the value may be indicated by an auditory information means, recording device or the combination thereof.
  • the control device 10 realized by the CPU 15 not only controls the processing of the measurement results, but also can infer optimal transmitting ultrasonic waves from the measurement results and control the pulse voltage generator 1.
  • the degree of oscillation of the implants was measured according to the present invention 3 to 4 months after the implants had been buried, an example in which the implant fell away was found among the examples whose degrees of oscillation were more than 30. Furthermore, in an example, since the degree of oscillation of one implant was high, that is, approximately 40 when it was buried, the implant was removed and another implant was buried. The degree of oscillation of the new implant was less than 20 and the subsequent progress thereof has been satisfactory.
  • An object whose degree of oscillation is measured according to the present invention is not limited to a dental implant.
  • two kinds of stainless screws (Screw A: 6 mm in diameter, 30 mm is length and 7 g in mass, Screw B: 3 mm in diameter, 6.5 mm in length and 0.6 g in mass) were screwed into holes of an apparatus having the mass of approximately 1 kg
  • the degree of oscillation of the screw A was 2 when the screw A was tightened and 5 when it was loosened.
  • the degree of oscillation of the screw B was 20 when the screw B was tightened and 50 when it was loosened.
  • the degree of oscillation varied in accordance with the degree of tightness of the screws.
  • the apparatus of the present invention first enables the measurement of the fixing state of a dental implant and so on as the degree of oscillation and the simple and precise judgement and evaluation of the fixing state of an object.

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  • Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Health & Medical Sciences (AREA)
  • Animal Behavior & Ethology (AREA)
  • Acoustics & Sound (AREA)
  • Oral & Maxillofacial Surgery (AREA)
  • Dentistry (AREA)
  • Epidemiology (AREA)
  • Biomedical Technology (AREA)
  • Engineering & Computer Science (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Biophysics (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Dental Tools And Instruments Or Auxiliary Dental Instruments (AREA)
  • Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)
US07/603,621 1989-11-06 1990-10-26 Oscillation degree measuring apparatus Expired - Fee Related US5161521A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP1288094A JPH03148032A (ja) 1989-11-06 1989-11-06 動揺度測定装置
JP1-288094 1989-11-06

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US (1) US5161521A (de)
EP (1) EP0427146B1 (de)
JP (1) JPH03148032A (de)
DE (1) DE69013118T2 (de)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5267985A (en) * 1993-02-11 1993-12-07 Trancell, Inc. Drug delivery by multiple frequency phonophoresis
US5353631A (en) * 1992-05-29 1994-10-11 Benthos, Inc. Analyzing internal pressure of a sealed container using frequency spectra
US5392779A (en) * 1991-04-11 1995-02-28 Imperial College Of Science, Technology & Medicine Testing implants
US5427105A (en) * 1991-08-01 1995-06-27 Krautkramer Gmbh & Co. Measuring procedure for the thickness of the mucous membrane of an alveolar process
WO1995033416A1 (en) * 1994-06-09 1995-12-14 Sonex International Corporation Ultrasonic bone healing device for dental applications
US5578756A (en) * 1994-06-17 1996-11-26 Railway Technical Research Institute And Co. Ltd. Method and apparatus for evaluating soundness of block-like structures
US5675074A (en) * 1996-01-16 1997-10-07 Benthos, Inc. Analyzing internal pressure of a closed container
US6176840B1 (en) * 1997-08-11 2001-01-23 Matsushita Electric Works, Ltd. Ultrasonic cosmetic treatment device
US6497151B1 (en) * 1999-12-20 2002-12-24 U.S. Pipe & Foundry Company Non-destructive testing method and apparatus to determine microstructure of ferrous metal objects
WO2006119243A2 (en) * 2005-04-29 2006-11-09 William Marsh Rice University Tool to detect structural integrity of implant

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2863448B2 (ja) * 1994-09-26 1999-03-03 哲生 宅野 歯の動揺度測定装置
US6392584B1 (en) * 2000-01-04 2002-05-21 Richard Eklund System and method for detecting and warning of potential failure of rotating and vibrating machines
CN1280619C (zh) * 2001-09-12 2006-10-18 西门子公司 用于检测一个机械电子系统的固有振动的方法和装置
JP2011005058A (ja) * 2009-06-27 2011-01-13 Nec Corp 機械特性測定装置および機械特性測定装置の使用方法
JP6016631B2 (ja) 2010-06-18 2016-10-26 株式会社ダイセル 光学異性体用分離剤

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Publication number Priority date Publication date Assignee Title
US4383446A (en) * 1980-04-02 1983-05-17 Eckhard Roeder Method for non-destructively testing construction elements
US4502329A (en) * 1982-04-07 1985-03-05 Mitsubishi Denki Kabushiki Kaisha Method for checking insulative condition of insulated windings used in electrical appliances
US4543827A (en) * 1982-07-12 1985-10-01 Sumitomo Rubber Industries Method for measuring physical properties of material
JPS61292553A (ja) * 1985-06-20 1986-12-23 Taisei Corp 建築用配管の目詰り診断方法

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS4939035B1 (de) * 1970-11-24 1974-10-22
US4062227A (en) * 1976-12-23 1977-12-13 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration CW ultrasonic bolt tensioning monitor
EP0181131A3 (de) * 1984-11-01 1987-05-20 Kent Scientific and Industrial Projects Limited Gerät zur Bestimmung der Resonanzfrequenz von Knochen
AT387286B (de) * 1986-12-19 1988-12-27 Avl Verbrennungskraft Messtech Verfahren und einrichtung zur bestimmung von schwingungseigenschaften sowie zum betreiben eines piezoelektrischen wandlers

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4383446A (en) * 1980-04-02 1983-05-17 Eckhard Roeder Method for non-destructively testing construction elements
US4502329A (en) * 1982-04-07 1985-03-05 Mitsubishi Denki Kabushiki Kaisha Method for checking insulative condition of insulated windings used in electrical appliances
US4543827A (en) * 1982-07-12 1985-10-01 Sumitomo Rubber Industries Method for measuring physical properties of material
JPS61292553A (ja) * 1985-06-20 1986-12-23 Taisei Corp 建築用配管の目詰り診断方法

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5392779A (en) * 1991-04-11 1995-02-28 Imperial College Of Science, Technology & Medicine Testing implants
US5427105A (en) * 1991-08-01 1995-06-27 Krautkramer Gmbh & Co. Measuring procedure for the thickness of the mucous membrane of an alveolar process
US5353631A (en) * 1992-05-29 1994-10-11 Benthos, Inc. Analyzing internal pressure of a sealed container using frequency spectra
US5267985A (en) * 1993-02-11 1993-12-07 Trancell, Inc. Drug delivery by multiple frequency phonophoresis
WO1995033416A1 (en) * 1994-06-09 1995-12-14 Sonex International Corporation Ultrasonic bone healing device for dental applications
US5496256A (en) * 1994-06-09 1996-03-05 Sonex International Corporation Ultrasonic bone healing device for dental application
US5578756A (en) * 1994-06-17 1996-11-26 Railway Technical Research Institute And Co. Ltd. Method and apparatus for evaluating soundness of block-like structures
US5675074A (en) * 1996-01-16 1997-10-07 Benthos, Inc. Analyzing internal pressure of a closed container
US6176840B1 (en) * 1997-08-11 2001-01-23 Matsushita Electric Works, Ltd. Ultrasonic cosmetic treatment device
US6497151B1 (en) * 1999-12-20 2002-12-24 U.S. Pipe & Foundry Company Non-destructive testing method and apparatus to determine microstructure of ferrous metal objects
WO2006119243A2 (en) * 2005-04-29 2006-11-09 William Marsh Rice University Tool to detect structural integrity of implant
WO2006119243A3 (en) * 2005-04-29 2009-04-16 Univ Rice William M Tool to detect structural integrity of implant

Also Published As

Publication number Publication date
EP0427146A1 (de) 1991-05-15
JPH03148032A (ja) 1991-06-24
EP0427146B1 (de) 1994-10-05
DE69013118T2 (de) 1995-05-11
DE69013118D1 (de) 1994-11-10

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